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Publication
Featured researches published by Kai-ming Li.
IEEE Geoscience and Remote Sensing Letters | 2011
Kai-ming Li; Xian-jiao Liang; Qun Zhang; Ying Luo; Hong-jing Li
The micromotion of a target will generate a micro-Doppler (m-D) effect in the frequency domain. The m-D effect is regarded as a unique property of the target, which has special significance in target detection, identification, and classification. The classical range-Doppler algorithm cannot obtain a clear inverse synthetic aperture radar (ISAR) image due to the m-D effect induced by micromotion dynamics. The m-D effect induced by periodical micromotion is represented as a sinusoidal modulation in a spectrogram, whereas the Doppler induced by a main body is depicted as the form of a straight line. Therefore, the extraction of an m-D signature is transformed into the separation of a sinusoid and a straight line. The cancellation technique is a classical method for removing ground clutter. Based on the same principle, the cancellation technique is applied to the spectrogram in this letter, which successfully achieves the separation of the m-D signature and gets the clearer ISAR image of the main body. The effectiveness and robustness of the algorithm are proved by simulation results.
Science in China Series F: Information Sciences | 2012
Feng Zhu; Qun Zhang; Ying Luo; Kai-ming Li; Fufei Gu
The random stepped frequency chirp signal (RSFCS) has better performance in anti-jamming than that of conventional stepped frequency chirp signal (SFCS). In combination with the theory of compressing sensing (CS), a novel ISAR imaging method is proposed based on RSFCS, in which the high resolution range profile (HRRP) is reconstructed by using the conventional OMP algorithm, whereas the cognitive approach is introduced to further reduce the number of sub-pulse in RSFCS. In the proposed method, via cognizing the characteristics of moving targets, the number of sub-pulse in each burst can be adjusted adaptively. Finally, in the cross-range direction, the accurate reconstruction of ISAR image by using CS theory is implemented, which can effectively accomplish unwrapping. With the proposed method, high quality HRRP and ISAR image can be achieved with fewer sub-pulses of RSFCS and lower burst repetition frequency (BRF). Some simulation results are given to validate the effectiveness and robustness of the proposed algorithm.
international conference on machine learning | 2017
Yi-shuai Gong; Qun Zhang; Kai-ming Li; Yi-jun Chen
Considering the need of multi-target imaging, a method about MIMO radar waveform optimization based on dynamic adjustment of signal bandwidth is proposed. At first, the closed-loop feedback between the range profile and the signal bandwidth is established, which can design the required bandwidth of transmit signal in different directions, according to the range profile of targets. And then, considering the request of beampattern and the bandwidth limitation, a waveform optimization model is established and solved. Therefore, the multi-target observation and the dynamic adjustment of the signal bandwidth are accomplished. What’s more, satisfactory imaging results are obtained under the least resource consumption. In the end, the simulation has proved the performance of the algorithm in low SNR circumstance.
IEEE Sensors Journal | 2017
Yi-jun Chen; Qun Zhang; Ying Luo; Kai-ming Li
The advantages of phased-MIMO technique have been utilized for multi-target imaging in the first part of this paper, and the better multi-target imaging performance has been shown compared with the traditional phased-array radar imaging and traditional MIMO radar imaging. For multi-target imaging, the limited radar resources should be allocated for different targets to achieve the maximal performance of radar. By establishing and solving a radar resource allocation optimization model, an adaptive resource allocation strategy for multi-target imaging based on phased-MIMO technique is proposed. With the method, the multi-target imaging efficiency can be improved significantly. The effectiveness of the proposed method is demonstrated by simulations.
IEEE Sensors Journal | 2017
Yi-jun Chen; Qun Zhang; Ying Luo; Kai-ming Li
Radar imaging provides the shape structure information for target recognition. In this paper, a multi-target radar imaging method based on the emerging phased-MIMO (multiple-input multiple-output) technique is proposed. Each single-element transmit antenna in traditional MIMO radar imaging system is replaced by a transmit array (TA), which operates in phased-MIMO mode. In the phased-MIMO mode, each TA is divided into several sub-arrays operating in phased-array radar mode, and the transmitted waveform by each sub-array is orthogonal to each other. The sub-arrays steer different transmit beams to different targets’ directions with optimized waveform for the corresponding target. The virtual aperture produced by the waveform diversity is used for coherent processing to improve the signal-to-noise ratio and the signal-to-interference ratio, and then the single-snapshot imaging for multi-target with high azimuth resolution can be achieved based on dictionary optimization and orthogonal matching pursuit. Simulation results indicate the effectiveness of the proposed method.
international geoscience and remote sensing symposium | 2012
Qun Zhang; Feng Zhu; Donghu Deng; Fufei Gu; Kai-ming Li
Aimed at the problem of how to diminish SAR raw data apparently and realize SAR imaging effectively, a new approach for processing SAR raw data combined with Linde-Buzo-Gray (LBG) algorithm and Compressed Sensing (CS) is proposed in this paper. For SAR returned signals, CS is engaged to reduce the sampling number in the pulse duration, and LBG algorithm as a classical vector quantization (VQ) method, is employed to diminish encode number of every sample value. Next, data reconstruction process still contains the two ordinal steps according to LBG algorithm and CS theory, respectively. On the basis of that, the traditional SAR imaging method, Frequency Scaling (FS) algorithm, is carried out to achieve the final SAR image. Simulation results show that the high quality SAR image can be achieved on condition of the SAR raw data is diminished furthermore obviously, which is compared with the traditional method.
Journal of Electronics Information & Technology | 2014
Bi-shuai Liang; Qun Zhang; Hao Lou; Sai Ma; Ying Luo; Kai-ming Li
sensor array and multichannel signal processing workshop | 2018
Guangming Li; Qun Zhang; Ying Luo; Kai-ming Li; Linghua Su; Rui Li
Iet Radar Sonar and Navigation | 2018
Qi-yong Liu; Qun Zhang; Ying Luo; Kai-ming Li; Li Sun
IEEE Geoscience and Remote Sensing Letters | 2018
Fufei Gu; Min-Hui Fu; Bi-Shuai Liang; Kai-ming Li; Qun Zhang